JP4629947B2 - Inhalation device with administration frequency counter - Google Patents

Description

[0001]
[Background technology]
The present invention relates to an inhaler for administering a medicine by inhalation. In particular, the present invention relates to a multi-dose dry powder inhaler device having a dosing counter that displays the number of metered doses of medication that has been dispensed from the medication container of the inhalation device or remaining.
[0002]
Administration of powdered drug by inhalation from an inhalation device is known. Typical inhalation devices include a pressurized metered dose inhaler (pMDI) having a container in which the particulate drug is suspended in a propellant gas and a dry powder inhaler having a powder drug container that does not use a propellant gas. There is a device (DPI).
[0003]
Various dose counters have been described for use in pressurized metered dose inhalers or dry powder inhalers. The dose counter generally helps the patient record the number of doses still available from the inhalation device, thereby alerting the patient when the inhaler is about to be exhausted. The dosing counter usually has the common feature of detecting relative movement between the drug container and the actuation and dosing member and increasing the number in response to such movement.
[0004]
For example, WO 86/05991 includes a counter wheel provided vertically on a horizontally pierced disc for administration, the counter wheel being a rotatable disc for administration. A multidose powder inhalation device having a dosing number counter that is rotated by a worm drive that forms part of the device is described.
[0005]
WO 97/20589 pamphlet is provided with a pair of coaxially arranged 1-th wheel, 10-th wheel, 100-th wheel, and the 1-th wheel is arranged in the longitudinal direction. There is a description of a multi-dose powder inhaler device having a dosing frequency counter driven by a spring plate connected to a slide for movable dosing.
[0006]
WO 92/00771 pamphlet includes a dosing number counter comprising a rotatable dosing member, a tape secured to the shaft of the metering member, and a tape wound on the shaft as the metering member rotates. There is a description of a dosing powder inhalation device. In another embodiment, the dosing frequency counter comprises a drive disk disposed coaxially with the counting ring and the metering member, the drive disk comprising a spring arm. When the drive disk completes one rotation, the spring arm moves in cooperation with a cam fixed to the storage unit and engaged with the counting disk.
[0007]
U.S. Pat. No. 5,687,710 describes a multi-dose powder inhaler device having a rotatable dosing plate and a dosing frequency counter with continuous and intermittent counting rings. The counting ring is provided coaxially and has a counting display (indicia) on its outer surface. The actuating means has a pawl for engaging the gear teeth of the continuous and intermittent counting ring.
[0008]
EP 488609 discloses a multi-dose powder inhalation device having a dosing frequency counter comprising a dosing member movable longitudinally and an actuating finger for rotating an indexing gear. There is a description. The index gear is connected to a gear wheel having a counting display unit through a worm drive.
[0009]
WO 94/11044 has a dosing counter with a rotatable dosing member, a ratchet wheel that moves in concert with the actuating means, an eccentric elliptical gear, and a lid plate with a counting display on the top. There is a description of a multiple dose powder inhalation device.
[0010]
The above-described structure has complicated operation parts, and thus has a problem that it is bulky and difficult to assemble and can be expensive to manufacture.
[0011]
The multi-dose powder inhaler sold under the EasyHaler trademark has a counter wheel with gear teeth and a counting indicator, which is driven by a pin extending from a rotatable metering member Is done. The counter wheel is rotatably provided on two arcuate bearing ribs and fits a circumferential groove formed near the periphery of the counter wheel. Although its structure is not simple, the bearing rib has a dual function of the bearing of the counter wheel and the brake, so that the counter wheel is susceptible to unintentional movement or clogging or jamming.
[0012]
There is a need for a powder inhaler with a dosing counter that avoids the above weaknesses. In particular, the counter unit should consist of a relatively few simple machine parts, should not require excessive space, and at the same time provide a reliable counting function.
[0013]
[Summary of the Invention]
The present invention provides a multi-dose powder inhalation device for administering a powder medicament by inhalation. Its multi-dose powder inhaler is
An inhaler body that constitutes a drug container containing a plurality of doses of powder drug
Air flow path through which air is drawn through the mouthpiece,
It is rotatable about an axis of rotation and has one or more recesses for administration in its periphery, containing a metered dose of powdered drug from a drug container in one position and in another position A metering drum that provides a metered dose of powder drug into the air flow path, and a dose counter that displays the number of metered doses of drug dispensed or stored from the drug container;
The administration frequency counter is
A counter wheel having a center hole, having a longitudinal axis substantially parallel to and spaced from the rotation axis of the measuring drum, and is rotatably provided on the bearing shaft. The bearing passes from the suction device body through the center hole. A counter wheel, the counter wheel having a counting indicia and a plurality of gear teeth thereon,
A drive pin extending from the metering drum to engage at least one of the gear teeth of the counterwheel for every complete rotation (one rotation) of the metering drum to rotate the counterwheel by an increased amount;
To maintain rotation in one direction and prevent unintentional movement of the counter wheel, it consists of a flexible brake finger that extends from the inhaler body and is adapted to engage the counter wheel.
[0014]
The dosing frequency counter of the present invention comprises a metering drum between a loading position for placing the medication in the recess of the metering drum for dosing and an inhalation position where the filled recess for dosing is carried to the air flow path. Stepwise rotation is detected. Preferably, the stepwise rotation of the metering drum is performed by means of a ratchet wheel. The ratchet wheel is suitably coaxial with the metering drum and is integrated with the metering drum as one piece.
[0015]
The ratchet wheel of the metering drum can be operated manually. Preferably, the ratchet wheel of the metering drum is driven by an operating member movable in the longitudinal direction. For example, the inhalation device can be actuated by movement on the axis of the depressible cover. In such an embodiment, the push-down cover is provided with an elongated pawl that is adapted to engage with the ratchet wheel of the metering drum, corresponding to each axial movement of the cover. A complete rotation of the metering drum is performed by reaching a predetermined number on the shaft of the cover, the number depending on the number of teeth on the ratchet wheel.
[0016]
The counter wheel is provided with a plurality of gear teeth and is provided with a relatively flat top, preferably having a counting display, typically alphanumeric characters. The gear teeth are engraved on the counter wheel in a suitable manner, such as on the outer periphery. In a preferred embodiment, the counter wheel comprises a circumferential skirt and the gear teeth are formed on the inner circumference of the skirt so that they face inwardly towards the axis of the counter wheel.
[0017]
The counter wheel is rotatably provided on a shaft of a bearing extending from the inhaler main body. In a preferred embodiment, the bearing shaft extends from the outer wall of the drug container. The counter wheel has a hole in the center, and the bearing shaft extends through the hole so that the counter wheel is supported by the bearing shaft. The counter wheel is provided adjacent to the metering drum so that the rotation axis of the counter wheel is substantially parallel to the rotation shaft of the metering drum, but is spaced apart.
[0018]
The counter wheel is driven by pins extending from the flat surface of the metering drum in the direction of the counter wheel. The part of the pin that engages the gear teeth of the counter wheel is generally provided off the axis of the metering drum so that the engagement only takes place with every complete rotation (or one rotation) of the metering drum. The pins are configured as gear teeth extending coaxially with the metering drum, with the gear teeth being separated from one another, leaving one. In such an embodiment, one remaining gear wheel tooth serves as the drive pin. In operation, the drive pin is brought into engagement with at least one gear tooth of the counter wheel so as to rotate the counter wheel by an increment for every complete rotation of the metering drum. The amount of increase generally corresponds to the number of teeth on the counter wheel. The number of pre-determined movements of the push-down cover that is necessary for the counter wheel to make a full rotation depends on the number of teeth on the ratchet wheel and the counter wheel. Typically, the counter wheel is intended to rotate only once during the life of the inhaler.
[0019]
Preferably, the gear teeth are formed only in a part around the inner circumference of the skirt portion of the counter wheel so that a gap is formed between the teeth facing the center. This prevents the counter wheel from moving past the last counting display indicating that the container is empty.
[0020]
A flexible brake finger extending from the inhaler body is preferably adapted to engage at least one of the gear teeth of the counter wheel. In a preferred embodiment of the present invention, the flexible brake fingers are adapted to engage simultaneously with the engagement of at least two non-adjacent gear teeth of the counter wheel. This prevents the counterwheel from sensing unintentional movements, and in particular the counterwheel is stable even where the brake fingers encounter the gap between the teeth of the counterwheel.
[0021]
The flexible brake finger can also be configured to engage an additional gear wheel located, for example, on the outer periphery of the counter wheel. In this embodiment, the counter wheel is provided with two gear wheels, one for increased rotation by the drive pin and the other for engagement by the brake finger.
[0022]
Preferably, the flexible brake finger is configured to have two curved surfaces and a bridge portion connecting the curved surfaces for simultaneous engagement with the engagement surfaces of at least two non-adjacent gear teeth. The
[0023]
Detailed Description of the Invention
The apparatus of the present invention is illustrated and described below with reference to FIGS.
[0024]
In FIG. 1, the structure of one embodiment of the device of the present invention is shown as an exploded view. The main parts of the apparatus are a main body 3, a mouthpiece 4, a push-down cover 6, a measuring drum 2 and a counter wheel 1. 3 and 4, the main body 3 constitutes a medicine container 8 filled with a powder medicine. The medicine container 8 has a square cross-sectional shape and has a conical end portion. The lid 5 closes the upper end of the medicine container. The push-down cover 6, together with a pair of elongated claws 9, functions as described later, but covers the drug container 6 and the lid 5. The spring 7 biases the push-down cover 6 to the upper stationary position. A rotatable counting drum 2 having five dosing recesses 10 is attached to a hollow cylindrical element 11 and a container integrally formed with the drug container 8 is typically for example for 200 doses. Has a drug supply.
[0025]
The body 3 also constitutes the rear wall 9 of the device together with a projection 12 that receives the mouthpiece 4 having an air flow path 13. The vertical face of the mouthpiece acts as the side wall of the device. A window 30 is provided on the vertical wall of the mouthpiece 4 and a part of the counter wheel 1 can be seen from the window. A flexible brake finger 33 extends from the wall 32 connecting the rear wall and the drug container, the function of which will be described later.
[0026]
In addition to a series of dosing recesses 10, the metering drum 2 has two series of five ratchet teeth 14 adapted to engage the elongated pawl 9 of the cover 6. The ratchet teeth 14 and the metering drum are molded as one part. The device operates by depressing the cover 6 so that the pawl 9 engaged with the teeth 14 rotates the metering drum 2 and the rotation corresponds to the peripheral distance between the recesses 10 for dosing. Is executed only in steps. Further, as better shown in FIG. 3, the cylindrical element 11 is adapted to engage with a notch 15 in the metering drum 2 so that the metering drum 2 can only be rotated in one direction. It has an extended pawl tip 16. The pawl tip 16 automatically aligns the dosing recess 10 with the outlet of the drug container on one side and the air flow path 13 of the mouthpiece 4 on the other side.
[0027]
Although the function of the counter wheel 1 will be described later, the counter wheel 1 has a center hole 17 and is rotatably provided on a bearing shaft 18 extending from the main body 3 of the inhaler.
[0028]
FIG. 2 is a longitudinal sectional view of the drug container 8 of the apparatus. The cylindrical body 11 has an opening 19, and when the administration recess 10 is aligned with the opening 19, the powder falls from the drug container 8 through the opening to the administration recess. Another opening 20 is provided at the height of the air channel 13 in order to release the powder from the administration recess to the air channel 13. In the position shown in FIG. 2, the upper dosing recess is just filled with powdered drug from the drug container 8, and the previously filled dosing recess rotates into the air channel 13 and is ready for dosing for inhalation. The The mouthpiece 4 is formed on one side of the inhalation device, from which powder can be inhaled. The mouthpiece has an air flow path 13 for dispensing drug administration from a dosing recess to a flow of breathing air. An air intake port 21 is provided in a region where the mouthpiece 4 is attached. The air taken in is guided into an elongated hole between the opening 20 of the cylindrical element 11 and the partition wall 22 of the mouthpiece 4. The elongated holes supply a strongly aligned air flow to the dosing recess and blow off the powder from the dosing recess to the air channel 13.
[0029]
The structure of the administration frequency counter of the device will be described with reference to FIGS. A bottom view and a cross-sectional view of the counter wheel 1 are shown in FIGS. The counter wheel has a flat top 23 and a circumferential skirt 24. The plurality of gear teeth 25 are formed on the inner circumference of the skirt portion 24, and the gear teeth 25 face the axis of the counter wheel inward. Each gear tooth 25 includes a shoulder 26 and a tapered portion 27. A counting display (not shown), for example a multiple of 10, is placed on the relatively flat top 23 of the counter wheel 1 and a part of the display can be seen through the window 30. The counter wheel 1 is provided with a central hole 17 extending through the counter wheel and a row of bosses 28 that support the counter wheel 1 on the bearing shaft 18. In the upper part 23 there is a protruding ring 29 for sliding contact with the vertical wall of the mouthpiece 4.
[0030]
FIG. 7 is a side view of the body 3, counter wheel 1 and metering drum 2 assembled together, the components being shown as transparent. The measuring drum 2 is inserted into the cylindrical element 11. The measuring drum is provided with a drive pin 31 and extends on the shaft in the direction of the counter wheel 1 from the flat surface of the measuring drum 2. The drive pin 31 is in the form of a small diameter gear wheel extending coaxially with the metering drum 2, with all but one other tooth of the gear wheel being cut apart.
[0031]
The counter wheel 1 is rotatably provided on the bearing shaft 18 and extends from the frame of the cylindrical element 11 in the vicinity of the outer wall of the medicine container 8. The center hole 17 and the alignment protrusion 28 of the counter wheel 1 are adapted to receive the bearing shaft 18, and the tip of the bearing shaft 18 extends to the level of the upper portion 23 of the counter wheel 1. The counter wheel 1 is adjacent to the measuring drum 2, and the rotating shaft of the counter wheel 1 is substantially parallel to the rotating shaft of the measuring drum 2 but is spaced apart.
[0032]
As shown in FIG. 7, the teeth of the drive pin 31 are adapted to engage with the shoulder portions 26 of the gear teeth 25 of the counter wheel 1. The portion of the drive pin 31 that engages the gear teeth 25 is provided off the axis of the metering drum so that the engagement occurs with every complete rotation of the metering drum 2. Since the metering drum has five ratchet teeth 14, the metering drum 2 performs one complete rotation (or one rotation) after five axial movements (operations) of the push-down cover 6. Thus, the drive pin 31 engages with one of the gear teeth 25 of the counter wheel 1 for every fifth operation and rotates the counter wheel 1 by an increment. The amount of increase depends on the number of gear teeth 25 of the counter wheel 1. The predetermined number of axial movements of the push-down cover 6 required for the counter wheel 1 to make a complete rotation is the number of ratchet teeth 14 of the metering drum 2 and the number of gear teeth 25 of the counter wheel 1. Dependent. In the configuration of FIG. 7, 200 or more operations are necessary for one complete rotation of the counter wheel 1.
[0033]
As best shown in FIG. 5, the gear teeth 25 are only on the inner circumferential portion of the skirt portion 24 of the counter wheel 1 so that a gap 34 is formed between the teeth of the plurality of gears. Is formed. After the drive pin 31 engages the last gear tooth 25 in front of the gap 34, the drive pin 31 cannot rotate the counter wheel 1 by the next or subsequent rotation. This means that after the last indicia indicating that the medicine container 8 is empty, the counter wheel 1 cannot be advanced by repeated operations. Further, after the last indicia, the rotation of the counter wheel 1 is prevented by means of a stop pin 35 adapted to engage a protrusion 36 extending from the outer wall of the drug container 8.
[0034]
A brake finger 33 that is slightly flexible in the direction of the bearing shaft 18 extends from the body 3 and has a longitudinal axis parallel to the rotational axis of the counter wheel 1. The flexible brake fingers 33 are adapted to engage the gear teeth 25 of the counter wheel 1 and maintain rotation in one direction of the counter wheel 1 to prevent unintentional movement. The engaging part of the brake finger 33 is configured to be able to engage simultaneously with the shoulders 26 of the two non-adjacent gear teeth 25 of the counter wheel 1. This ensures that the counter wheel 1 is stable where the brake fingers 33 encounter the gap 34 between the teeth of the counter wheel. This is accomplished by molding the engagement portion of the brake finger 33 into the shape of two curved surfaces 37 and a bridge portion connecting the surfaces 37.
[0035]
Those skilled in the art will recognize that modifications and variations can be made to the form and details of the disclosed embodiments without departing from the spirit and scope of the invention as defined in the following claims. Let's go. Making such modifications to the apparatus of the present invention is considered routine for those skilled in the art.
[Brief description of the drawings]
FIG. 1 is an exploded view of one embodiment of the apparatus of the present invention.
FIG. 2 is a longitudinal cross-sectional view through the drug container of the apparatus of FIG.
FIG. 3 is a front view of a main body part of the inhaler of FIG.
4 is a side view of the main body part of the inhaler of FIG. 1. FIG.
FIG. 5 is a bottom view of the counter wheel of the inhaler of FIG.
FIG. 6 is a cross-sectional view of the counter wheel of FIG.
7 is an assembled side view of the main body, counter wheel, and metering drum of the inhaler of FIG. 1, with parts depicted as transparent.

Claims (13)

A multi-dose powder inhalation device for administering a powder medicament by inhalation, comprising:
An inhaler body (3) constituting a drug container (8) for accommodating a plurality of doses of powder drug;
An air channel (13) through which air is drawn through the mouthpiece (4),
Rotating about an axis of rotation and having one or more recesses (10) for administration in its periphery, at one position for receiving a metered dose of powder drug from a drug container (8) And a metering drum (2) that provides a metered dose of powdered drug to the air flow path (13) at other locations, and a drug dispensed from or remaining in the drug container (8). A dose counter that displays the number of doses weighed,
The administration frequency counter is
A counter wheel (1) having a central hole (17), rotatably mounted on a bearing shaft (18) having a longitudinal axis substantially parallel and spaced apart from the rotational axis of the metering drum (2); The bearing shaft (18) extends from the inhaler body (3) through a central hole (17), and the counter wheel (1) has a counting display thereon and a plurality of gear teeth (25). , Counter wheel (1),
To rotate only increase the counter wheel (1), per revolution of the metering drum (2), so as to engage at least one tooth (25) of the plurality of gears of the counter wheel (1), metering A drive pin (31) extending from the drum (2);
A flexible brake finger (33) that extends from the inhaler body and is adapted to engage the counter wheel (1) to maintain rotation in one direction and prevent unintentional movement of the counter wheel (1)
A multiple dose powder inhaler device comprising:   Inhalation device according to claim 1, wherein a flexible brake finger (33) is adapted to engage at least one of a plurality of gear teeth (25) of the counter wheel (1).   Inhalation device according to claim 1, wherein the flexible brake finger (33) is adapted to engage simultaneously with the engagement portion (26) of at least two non-adjacent gear teeth (25) of the counter wheel (1). .   Two curved surfaces (37) for simultaneous engagement with engaging portions of at least two non-adjacent gear teeth (25), and said curved surfaces (37) The inhaler according to claim 3, further comprising a bridge portion that connects the two.   Inhalation device according to claim 1, wherein the outer circumference of the counter wheel (1) has an upper part (23) and a circumferential skirt part (24).   6. Inhalation device according to claim 5, wherein the gear teeth (25) of the counter wheel (1) are in the form of teeth directed towards the center formed around the inner circumference of the skirt part (24).   The inhaler according to claim 6, wherein the teeth are formed only in a part around the inner circumference so that a gap (34) is formed between the teeth facing the center.   Inhaler according to claim 1, wherein the counting display is provided on the upper part (23) of the counter wheel (1).   2. Inhalation device according to claim 1, wherein the bearing shaft (18) extends from the outer wall of the medicament container (8).   Inhalation device according to claim 1, wherein the metering drum (2) comprises integrated ratchet teeth (14) for stepwise rotation of the metering drum (2).   2. Inhalation device according to claim 1, comprising a push-down cover (6) for operating the inhalation device by means of an axial movement of the push-down cover (6).   12. The push-down cover (6) comprises an elongate pawl (9) adapted to engage with a ratchet tooth (14) of the metering drum (2) for each axial movement of the push-down cover (6). Inhalation device. 12. Inhalation device according to claim 11, wherein one rotation of the metering drum (2) is carried out by performing a predetermined number of axial movements of the push-down cover (6).

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